@JeremyCherfas Ah, so that's what uptalk sounds like! It's weird.
When I hear it, though, it comes across like a generalization of the prosody I use when reading a series. Something like, "They walked long; they walked far; they walked wide; but they found nothing," would have similar rises at the end of each clause in the series except the last.
Uptalk: Triumph of the Semicolon